Refrigerator ice and liquid dispenser incorporating imaging system

ABSTRACT

A safety system for an ice and liquid dispenser of a refrigerator is used to sense the presence of human skin in a dispensing well. The safety system includes a digital image capture device focused on a dispenser well for capturing images of objects, such as hands, in the dispenser well and a digital image analyzer operatively coupled to the digital image capture device. The digital image analyzer evaluates the digital images captured by the digital image capture device to determine if human skin color is detected in the image of the object in the dispensing well. If human skin color is detected, thus indicating a hand in the dispensing area, any dispensing operation will be prevented and an alert will be provided.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to the art of refrigerators and, moreparticularly, to incorporating an imaging system for a refrigerator iceand liquid dispenser.

2. Description of the Related Art

Modern refrigeration mechanisms, such as refrigerator/freezer units,have electrically powered actuators that perform a variety of functions.An example is an ice maker/dispenser. Normally, electrical motorsperform functions such as operating valves to supply water to the icemaker, moving a rod or rack to eject ice that has been frozen fromsupplied water, and moving other structure to convey, alter or directice pieces to an ice delivery or dispensing chute.

In the case of an ice maker/dispenser, a user normally must manuallypush a button with a finger or move a glass or container against a leverto actuate a motor to dispense ice down the chute. In some models, theuser can also manually push a button to select between ice cubes orcrushed ice and, in some instances, shaved ice. Normally, once actuated,the dispenser operates until the user releases the button or lever. Insome cases, the dispenser motor continues until automatically stopped bya timer.

In either of these cases, there are situations where it may be desirableto activate a warning signal or provide some form of notification whenan unusual activity occurs during a dispensing operation. For example,if a child reaches into the ice dispensing area or the ice dispensingchute, it may be appropriate to provide a signal to the child or anearby adult. To this end, it would be advantageous to automaticallydetect the presence of a human hand and activate a warning signal untilthe situation can be resolved. This would be particularly advantageousin refrigerators that have an ice crushing system located just above theice chute.

One example of a solution to the aforementioned problem is disclosed inU.S. Pat. No. 3,640,089 to Frazier. The Frazier patent discloses adispenser and crusher having a safety system for stopping operation ofthe dispenser and crusher upon the thrusting of an arm or otherelongated member into a chute region. The safety system includes aproximity detection circuit having a sensing plate associated with theice passage. However, Frazier does not distinguish between a human handand other objects that may be inserted into the ice chute.

Regardless of the existence of various known devices and methods fordetecting foreign objects in an ice chute, there is still a need forfurther advancements in ice and liquid dispenser control. Morespecifically, there exists a need for a more versatile ice and liquiddispenser safety system that employs digital imaging technology andwhich is capable of sensing the presence of human skin, thus a humanhand, in the dispensing area.

SUMMARY OF THE INVENTION

The present invention is concerned with a refrigerator including acabinet having top, bottom, rear and opposing side walls thatcollectively define a refrigerator body having a freezer compartment.The refrigerator further includes a door mounted to the cabinet forselectively providing access to the freezer compartment. The freezercompartment is provided with an ice maker, with the formed ice beingstored in an ice cube storage bin. An ice crushing mechanism and icechute are provided below the ice storage bin for dispensing ice to aservice station. In accordance with the invention, the refrigeratoremploys an ice and liquid dispensing control system that utilizesdigital images to determine if a person has inserted his or her handinto the dispensing station.

More specifically, the ice and liquid dispensing control system employsa digital image capture device which is focused upon a well of thedispensing station. The digital image capture device captures digitalimages of objects that enter an upper region of the dispensing well. Thedigital images are sent to a digital image analyzing system thatanalyzes the image to determine if human skin color is present in theimage.

In further accordance with the present invention, if the digital imagecapture device determines that human skin color is present in the image,a controller signals a user interface to generate audible or visualnotifications that a person has inserted his or her hand into an upperregion of the ice and liquid dispensing well.

Additional objects, features and advantages of the present inventionwill become more readily apparent from the following detaileddescription of preferred embodiments when taken in conjunction with thedrawings wherein like reference numerals refer to corresponding parts inthe several views.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a front elevational view of a refrigerator incorporating anice and liquid dispensing system incorporating an imaging systemconstructed in accordance with the present invention;

FIG. 2 is a fragmentary perspective view illustrating a freezercompartment of the refrigerator with the freezer door open;

FIG. 3 is a fragmentary, side sectional view of the ice and liquiddispensing system of FIG. 1;

FIG. 4 is a block diagram illustrating a digital image capture device ofthe imaging system used to capture images of objects that enter thedispensing area in accordance with the present invention; and

FIG. 5 is a flow chart illustrating the dispensing method according tothe present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

With initial reference to FIG. 1, a refrigerator constructed inaccordance with the present invention is generally indicated at 2.Refrigerator 2 includes a cabinet 4 having a top wall 6, a bottom 7 andopposing side walls 8 and 9. In a manner known in the art, refrigerator2 includes a freezer compartment 11 arranged along side a fresh foodcompartment 12. Freezer compartment 11 includes a corresponding freezercompartment door 14 and fresh food compartment 12 includes acorresponding fresh food compartment door 15. In a manner also known inthe art, each door 14, 15 includes an associated handle 17, 18.Refrigerator 2 is also shown to include a kick plate 20 arranged at abottom portion thereof having a vent 21 that permits air to flow intorefrigeration components (not shown) that establish and maintain desiredtemperatures in freezer compartment 11 and fresh food compartment 12. Inthe embodiment shown, refrigerator 2 constitutes a side-by-side model.However, it should be understood that the present invention could alsobe employed in connection with a wide variety of refrigerators,including top mount, bottom mount, and French-style refrigerator models.

As illustrated in FIG. 2 an ice making assembly 22 is disposed withinthe freezer compartment 16 and may be mounted to top wall 24 of thefreezer compartment 16 as shown, to a side wall, or on freezer door 20,with each of these mounting arrangements also being known in the art.Preferably, ice making assembly 22 takes the form of a conventional icepiece making apparatus and produces generally crescent shaped ice piecesas depicted in FIG. 2. The ice makers disclosed in U.S. Pat. Nos.4,649,717 and 5,160,094, herein incorporated by reference, areillustrative of the type of ice makers which may be used in accordancewith the present invention.

An ice dispensing system 26, mounted to the freezer door 20, is providedbelow the ice making assembly 22 for receiving ice pieces. The icedispensing system 26 includes an ice bucket or bin 28, as well as alower ice crushing system 30. When operated, the ice dispensing system26 transfers ice pieces from bin 28 to ice crushing system 30 and thenthrough the freezer door 14 whereby ice pieces may be dispensed througha forwardly exposed, external ice and liquid dispenser station or area31. More particularly, as shown in FIG. 3, an auger 32 positioned withinice bucket 28 causes the ice pieces to pass through an inlet opening andfall into the ice crushing region 30. Rotation of auger 32 rotatescrushing blades 35 resulting in the ice pieces being crushed. Thecrushed ice pieces, once past blades 35, fall through an outlet opening38. Once the ice pieces, in either a whole or crushed form, are passedthrough the ice outlet opening 38, they fall through an ice chute 40formed into the freezer door 14 to a waiting receptacle positionedwithin the service area 31. Ice chute 40 includes an entry end 41positioned adjacent to crushing blades 35 and an ice dispensing end 42positioned to eject ice into the service area 31.

In accordance with the invention, external ice and liquid dispenserstation 31 includes a main housing 44 and a control panel 49. Controlpanel 49 includes first and second rows of control buttons 53 and 54which enable a user to select a preferred dispensing operation. Controlpanel 49 further includes a display 57, such as an LCD display, which,in addition to functioning in cooperation with external ice and liquiddispenser station 31, enables the user to select particular operationalparameters for refrigerator 2, such as desired temperatures for freezercompartment 11 and fresh food compartment 12. In any case, external iceand liquid dispenser station 31 includes a dispenser well 63 having abase or container support portion 65 and a recessed, upstanding wallsection 68. Refrigerator 2 also includes an ice and liquid dispensercontrol system 75 for recognizing and sending an alert when a hand is inthe dispensing well or ice chute.

Dispenser control system 75 automatically detects when a user hasinserted a body part, particularly a hand, into at least an upper rearportion of dispenser well 63, particularly dispensing chute 40. Towardsthat end, dispenser control system 75 includes a digital image capturedevice 78 and a digital image analyzer 80, each of which is operativelycoupled to a controller 85. Basically, digital image capture devicedetects and images objects which enter dispenser well 63. Digital imagesfrom digital image capture device 78 are passed to digital imageanalyzer 80 which calibrates the image and performs color and thresholdbased segmentation of the image in order to detect the presence of skincolor in the image. If digital image analyzer 80 determines that humanskin color is present in the image, the results are sent back tocontroller 85 which produces a signal to alert those nearby that a childor other user has inserted his or her hand into at least an upper rearregion of dispenser well 63, including dispensing chute 40. The signalis preferably visually presented on display 57, but may include anaudible signal. In addition, controller 85 prevents any dispensingoperation. In the event that digital image analyzer system 80 determinesthat human skin color is not found on the image, controller 85 enablesdispensing to occur, such as through the operation of ice dispensingsystem 26. However, if during the dispensing process, an updated imagereveals a hand is now present, the dispensing process will be disabled.

As best shown in FIG. 4, digital image capture device 78 preferablyconstitutes a digital camera that can take on a variety of forms, suchas a fixed image charged/coupled device (CCD) camera, a fixed imagecomplimentary metal oxide semiconductor (CMOS) camera or even a videocamera. Digital image capture device 78 is preferably operativelyconnected to a light source 90 which produces light of one or morewavelengths. That is, light source 90 can bathe dispenser well 63 inwhite light, colored light or non-visible light depending upon aparticular parameter of interest. In any case, digital image capturedevice 78 is angled and operated to capture digital images of objectsthat enter dispenser well 63. Objects in dispenser well 63 arecontrasted against a reference image, e.g., the background of dispenserwell 63, for clarity. In the depicted embodiment, digital image capturedevice 78 is positioned in an upper portion of dispenser well 63 tocapture a side view of objects which may be above a container 91.

In accordance with a preferred control arrangement represented in FIG.5, digital image capture device 78 first takes a photograph, i.e.,captures a digital image, of an object that enters dispenser well 63 asshown in block 100. The digital image is analyzed by digital imageanalyzing system 80 to determine if skin is present in the image. Morespecifically, an image processing algorithm is carried out to determineif skin is detected in the image. That is, in block 105, the image isfirst subjected to an image correction step to correct distortions inthe image, such as distortions that result from the use of a fish eyelens in image capture device 78. The corrected image then undergoescolor based segmentation and threshold based segmentation as shown inblock 110. Following segmentation, the image segments are subjected to aclustering process in block 115 to determine a mean cluster. Theresulting images are then analyzed to determine if skin color isdetected in block 120. More specifically, the disclosed embodimentdetermines if the mean cluster is greater than a predeterminedthreshold. If the threshold is exceeded, there is an indication of skincolor in the image and dispensing is prevented (step 125). If the meancluster is not greater than the threshold, the control system enables adispensing operation (also step 125). Although not shown in this figure,if the threshold is exceeded, a signal is also preferably passed todisplay 54 in connection with step 125 to provide notice that humanskin, presumably a hand, is present in dispenser well 63.

Based on the above, it should be readily understood that the presentinvention enables a refrigerator to automatically detect and provide analert when a human hand or the like has been inserted into thedispensing well. In addition to sending an alert, the system of thepresent invention provides for the automatic shut down of the dispensingsystem if the presence of a hand is detected. Although described withreference to preferred embodiments of the invention, it should bereadily understood that various changes and/or modifications can be madeto the invention without departing from the spirit thereof. Forinstance, it should be understood that the number and location ofcameras can vary in accordance with the present invention. For example,cameras can be located within or simply exposed to the ice chute tocapture digital images. In general, the invention is only intended to belimited by the scope of the following claims.

What is claimed is:
 1. A refrigerator comprising: a cabinet including atleast one refrigeration compartment; a door mounted to the cabinet forselectively providing access to the refrigeration compartment; adispenser provided in the door for selectively performing a dispensingoperation, said dispenser including a dispenser well; a digital imagecapture device exposed to said dispenser well for capturing digitalimages of objects introduced into said dispenser well; a digital imageanalyzing system operatively connected to the digital image capturedevice, said digital image analyzing system being adapted to evaluatethe digital images captured by the digital image capture device todetermine a presence of human skin in said digital images; and acontroller for regulating the dispensing operation based on an output ofthe digital image analyzing system.
 2. The refrigerator according toclaim 1, wherein the controller prevents the dispensing operation whenthe output of the digital image analyzing system indicates the presenceof human skin in the dispensing well.
 3. The refrigerator according toclaim 1, wherein said digital image analyzing system is adapted todetermine the presence of human skin in the digital images by detectinga color of human skin.
 4. The refrigerator of claim 3, wherein thedigital image analyzing system employs image segmentation to distinguishobjects in the dispensing well.
 5. The refrigerator according to claim1, further comprising: an icemaker disposed within the refrigerationcompartment for producing ice cubes; an ice bucket for receiving icecubes produced by the icemaker; an ice crushing mechanism provided toselectively crush ice cubes from the ice bucket; and an ice chuteprovided in the door for delivering ice from the ice crushing mechanismto the dispenser, said ice chute having an ice entry end and an icedispensing end, said digital image capture device being exposed to takethe digital images directly adjacent the ice dispensing end of the icechute, wherein the controller prevents operation of the ice crushingmechanism when the output of the digital image analyzing systemindicates the presence of human skin in the dispensing well.
 6. Therefrigerator according to claim 1, wherein the digital image capturedevice constitutes a still image camera.
 7. The refrigerator accordingto claim 6, wherein the digital image capture device is acharged/coupled device (CCD) camera.
 8. The refrigerator according toclaim 6, wherein the digital image capture device is a complementarymetal oxide semiconductor (CMOS) camera.
 9. The refrigerator accordingto claim 1, wherein the digital image capture device constitutes a videocamera for capturing video images.
 10. The refrigerator according toclaim 1, wherein the digital image capture device includes a lightsource for illuminating the dispenser well for imaging purposes.
 11. Therefrigerator according to claim 1, wherein the digital image capturedevice is mounted at one side in the dispensing well.
 12. Therefrigerator according to claim 1, further comprising: an alertsignaler, wherein the controller provides an alert signal when theoutput of the digital image analyzing system indicates the presence ofhuman skin in the dispensing well.
 13. A method of controlling adispensing operation in a dispenser well of a refrigerator comprising:capturing an image of an object in the dispensing well; processing saidimage to determine if human skin is detected in said image; andcontrolling the dispensing operation when human skin is detected in theimage.
 14. The method of claim 13, wherein controlling the dispensingoperation constitutes preventing the dispensing operation or stoppingthe dispensing operation if human skin is detected during the dispensingoperation.
 15. The method of claim 14, wherein the refrigerator includesan icemaker, an ice crushing mechanism and a chute leading from an inletat the ice crushing mechanism to an outlet at the dispensing well, saidimage being captured directly adjacent the outlet.
 16. The method ofclaim 13, further comprising: automatically generating an alert signalif human skin is detected in the image.
 17. The method of claim 13,wherein processing said image includes segmenting the image.
 18. Themethod of claim 13, further comprising: operating a light source toilluminate the object in the dispensing well for imaging purposes. 19.The method of claim 18, wherein processing said image to determine ifhuman skin is detected in said image includes detecting a color of humanskin in the image.